Optical film

Abstract

An optical film according to various embodiments of the present invention may include a base portion; a pyramid pattern layer wherein a plurality of pyramid patterns having a vertex angle being in the vertex angle range of 60° or larger to 160° or smaller is formed on one surface of the base portion; and a diffusion layer wherein a plurality of optical protrusion patterns formed on the other surface of the base portion. the pyramid pattern layer is formed to have a refractive index greater than or equal to a refractive index of the diffusion layer, and a haze value of the diffusion layer is 15% or higher.

What is claimed is: 
     
         1 . An optical film comprising:
 a first sheet including a first base portion; a pyramid pattern layer wherein a plurality of pyramid patterns is formed on one surface of the first base portion; and a first diffusion layer wherein a plurality of first optical protrusion patterns formed on the other surface of the first base portion;   a second sheet disposed over the first sheet and including a second base portion; a first prism pattern layer wherein a plurality of first prism patterns is formed on one surface of the second base portion; and a second diffusion layer wherein a plurality of second optical protrusion patterns having adhesiveness are formed on the other surface of the second base portion; and   a third sheet disposed over the second sheet and including a third base portion; a second prism pattern layer wherein a plurality of second prism patterns is formed on one surface of the third base portion; and a third diffusion layer wherein a plurality of third optical protrusion patterns having adhesiveness are formed on the other surface of the third base portion,   wherein the pyramid pattern layer is formed to have a refractive index greater than or equal to a refractive index of the first diffusion layer,   wherein a haze value of the first diffusion layer is 15% or higher; and   wherein the first sheet and the second sheet are laminated by the second optical protrusion patterns having adhesiveness of the second diffusion layer, and the second sheet and the third sheet are laminated by the third optical protrusion patterns having adhesiveness of the third diffusion layer.   
     
     
         2 . The optical film of  claim 1 , wherein the plurality of first optical protrusion patterns of the first diffusion layer are configured to be a matte pattern. 
     
     
         3 . The optical film of  claim 1 , wherein the plurality of first optical protrusion patterns of the first diffusion layer are configured to be a reverse prism pattern. 
     
     
         4 . The optical film of  claim 1 , wherein the plurality of pyramid patterns of the pyramid pattern layer are configured to be intaglio. 
     
     
         5 . The optical film of  claim 1 , wherein a perpendicular cross-section of the plurality of pyramid patterns which is parallel to a height direction of the optical film is an isosceles triangle. 
     
     
         6 . The optical film of  claim 1 , wherein a vertex angle of the plurality of pyramid patterns of the pyramid pattern layer is in the vertex angle range of 60° or larger to 160° or smaller. 
     
     
         7 . The optical film of  claim 6 , wherein a vertex angle of the plurality of pyramid patterns of the pyramid pattern layer is in the vertex angle range of 80° or larger to 130° or smaller. 
     
     
         8 . The optical film of  claim 1 , wherein a deviation between a refractive index of the pyramid pattern layer and a refractive index of the second diffusion layer is 0.05 or less. 
     
     
         9 . The optical film of  claim 1 , wherein a deviation between a refractive index of the first prism pattern layer and a refractive index of the third diffusion layer is 0.05 or larger. 
     
     
         10 . The optical film of  claim 1 , wherein a pitch of the pyramid pattern layer is formed to have a predetermined multiple deviation from an integer multiple of a pitch of the first prism pattern layer and a pitch of the second prism pattern layer. 
     
     
         11 . An optical film comprising:
 a base portion; a pyramid pattern layer wherein a plurality of pyramid patterns having a vertex angle being in the vertex angle range of 60° or larger to 160° or smaller is formed on one surface of the base portion; and a diffusion layer wherein a plurality of optical protrusion patterns formed on the other surface of the base portion,   wherein the pyramid pattern layer is formed to have a refractive index greater than or equal to a refractive index of the diffusion layer, and   wherein a haze value of the diffusion layer is 15% or higher.   
     
     
         12 . The optical film of  claim 11 , wherein the plurality of optical protrusion patterns of the diffusion layer are configured to be a matte pattern. 
     
     
         13 . The optical film of  claim 11 , wherein the plurality of optical protrusion patterns of the diffusion layer are configured to be a reverse prism pattern. 
     
     
         14 . The optical film of  claim 11 , wherein a vertex angle of the plurality of pyramid patterns of the pyramid pattern layer is in the vertex angle range of 80° or larger to 130° or smaller. 
     
     
         15 . The optical film of  claim 11 , wherein the plurality of pyramid patterns of the pyramid pattern layer are configured to be intaglio. 
     
     
         16 . A backlight unit comprising:
 a light source;   a color conversion sheet; and   an optical film disposed over the color conversion sheet and further comprising:   a fourth sheet including a fourth base portion; a pyramid pattern layer wherein a plurality of pyramid patterns with a vertex angle being in the vertex angle range of 60° or larger to 160° or smaller is formed on one surface of the fourth base portion; and a fourth diffusion layer wherein a plurality of fourth optical protrusion patterns formed on the other surface of the fourth base portion;   a fifth sheet disposed over the fourth sheet and including a fifth base portion; a third prism pattern layer wherein a plurality of third prism patterns is formed on one surface of the fifth base portion; and a fifth diffusion layer wherein a plurality of fifth optical protrusion patterns having adhesiveness are formed on the other surface of the fifth base portion; and   a sixth sheet disposed over the fifth sheet and including a sixth base portion; a fourth prism pattern layer wherein a plurality of fourth prism patterns is formed on one surface of the sixth base portion; and a sixth diffusion layer wherein a plurality of sixth optical protrusion patterns having adhesiveness are formed on the other surface of the sixth base portion,   wherein the pyramid pattern layer is formed to have a refractive index greater than or equal to a refractive index of the fourth diffusion layer,   wherein a haze value of the fourth diffusion layer is 15% or higher; and   wherein the fourth sheet and the fifth sheet are laminated by the fifth optical protrusion patterns having adhesiveness of the fifth diffusion layer, and the fifth sheet and the sixth sheet are laminated by the plurality of sixth optical protrusion patterns having adhesiveness of the sixth diffusion layer.   
     
     
         17 . The backlight unit of  claim 16 , wherein the plurality of fourth optical protrusion patterns of the fourth diffusion layer are configured to be a matte pattern. 
     
     
         18 . The backlight unit of  claim 16 , wherein the plurality of fourth optical protrusion patterns of the fourth diffusion layer are configured to be a reverse prism pattern. 
     
     
         19 . The backlight unit of  claim 16 , wherein the plurality of pyramid patterns of the pyramid pattern layer are configured to be intaglio. 
     
     
         20 . The optical film of  claim 16 , wherein a pitch of the pyramid pattern layer is formed to have a predetermined multiple deviation from an integer multiple of a pitch of the third prism pattern layer and a pitch of the fourth prism pattern layer.